Omron SYSMAC CS Series Operation Manual page 149

Zero/Span Adjustment Example
Output Units
1,2,3... 1. Set an analog output value equivalent to 0% in the CPU Unit's CIO Area. Check the signal using
the calibration device. If the value is abnormal, change the zero adjustment value in the DM Area,
and adjust the offset (parallel movement) value.
2. Set an analog output value equivalent to 100% in the CPU Unit's CIO Area. Check the signal using
the calibration device. If the value is abnormal, change the span adjustment gain value in the DM
Area, and adjust the gain (bias).
Adjust the zero/span according to the following equation.
Process value after adjustment = (input value – minimum process value in range) x DM Area span adjustment
gain value + minimum process value in range + DM Area zero adjustment value
Example: Minimum process value in range = 0; maximum process value in range = 4,000; span adjustment
gain = 10060 x 0.0001 = 1.0060; zero adjustment value = 5
If the input value is 500, the process value after adjustment will be as follows:
Process value after adjustment = (500 – 0) x 1.0060 + 0 + 5 = 508.
Process value (after adjustment = stored data)
4600 (115%)
4000 (100%)
508
5
0 (0%)
−600 (−15%)
136
−600
0 500
Span adjustment gain (example: 1.006)
Zero adjustment value (example: 5)
Process value (before adjustment)
4000 4600
Appendix B